Should you be afraid of EBV?
By Sydney Saltzman
If you are an adult reading this blog post, there is over a 90% chance that you have been infected with the Epstein-Bar virus (EBV) at some point in your life. Maybe you were one of the lucky individuals who did not experience any symptoms accompanying their infection. Or maybe you were one of the not-so-lucky individuals whose EBV infection caused infectious mononucleosis (more commonly referred to as ‘mono’), and you were rendered out of commission for a few weeks because of the fatigue and body aches. Either way: no harm, no foul. No need to become too concerned with a super common virus, with symptoms that mostly mimic a common cold, right?
Well, not exactly. Long after your cold symptoms (if you even experienced any) have subsided and you’re back at school or work, the genetic material of the Epstein-Bar virus is still waiting latent in your cells. This presents the opportunity for EBV to cause far more serious illness long after the initial infection. Examples of these illnesses may include certain cancers and Multiple Sclerosis.
It has been known for some time that Epstein-Bar Virus has been linked to certain cancers including Hodgkin Lymphoma, Gastric carcinoma, and Nasopharyngeal carcinoma. It’s the mechanisms the Epstein-Bar virus uses to cause different types of cancer that researchers are still working to understand. One recent study proposes that a protein that is created by the Epstein-Bar virus’s DNA is responsible for initiating a series of steps that inactivates a tumor suppressor gene in the host. The inactivation of the tumor suppressor gene essentially removes one of the cell’s mechanisms for preventing uncontrolled cell division, and thus makes the host more susceptible to the formation of tumors. Researchers found that when Epstein-Bar virus DNA was missing the gene that creates this protein, the tumor suppressor gene was still expressed by the test host cells infected with the virus. When the Epstein Bar virus DNA responsible for making the protein was reintroduced into the test cells, the protein was synthesized in the test host cells, and the cells no longer expressed the tumor suppressor gene. This research suggests that the Epstein-Bar virus DNA that remains latent in the host long after the initial infection is still capable of causing serious illness.
A link between EBV and the autoimmune disease, Multiple Sclerosis (MS) has also been found by researchers. According to data collected in a recent review article, one study found that 99.5% of Multiple Sclerosis patients tested positive for the Epstein-Bar virus, while only 94% of the non-afflicted control group tested positive for the virus. This suggests that there is a higher likelihood of being afflicted with Multiple Sclerosis if a patient has previously been infected with Epstein-Bar virus. Although the exact nature of the relationship between the virus and the disease is unknown, another study presented in the review article suggests that an antibody which is created by the host to detect a specific Epstein-Bar virus protein in the host’s cells, is present in elevated levels in MS patients. Research also found that the amount of these antibodies found in a patient’s blood, correlates with the progression of Multiple Sclerosis in that patient, as patients with more antibodies exhibited more demyelinated regions in their brain (an effect of Multiple Sclerosis). This data further suggests that the viral genetic material the EBV leaves in its host cells can have more serious long-term effects than we may initially presume.
Now that we know it would be remiss to write-off Epstein-Bar virus as completely benign, this raises the question: how concerned should we be about the virus? According to the organization Cancer Research UK, between 110,000 and 200,000 cancer cases worldwide are linked to EBV infection. While this may seem like a large number, it is important to put this number in perspective. In the US alone, in 2015, it is projected that close to 1.7 million people will be diagnosed with cancer, which makes the number of cases on EBV-related cancers worldwide seem much less daunting. There is also wealth of available information that suggests that individuals with compromised immune systems are at higher risk of EBV-related cancers than otherwise healthy individuals who are infected with Epstein-Bar virus. As for the link between Epstein-Bar virus and Multiple Sclerosis, the author of aforementioned review article notes that, while EBV infection maybe a prerequisite for developing Multiple Sclerosis, there are other factors that also come into play. This means that Epstein-Bar virus infection alone is not enough to determine whether a patient will develop Multiple Sclerosis. While this information suggests that we should be mindful of the Epstein-Bar virus and its potential to cause serious illness, there is no need to go into a full-blown panic. While there is currently an EVB vaccine in trial stages, for now, maybe the most important thing we can do to combat the virus is to be aware of the fact that it is most commonly spread through saliva. With this in mind, maybe we should think twice about whom we share our food and drinks with, and even whom we kiss.
 “About Epstein-Barr Virus (EBV),” Centers for Disease Control, http://www.cdc.gov/epstein-barr/about-ebv.html (January 6, 2014)
 “Developing a vaccine for the Epstein-Barr Virus could prevent up to 200,000 cancers globally say experts,“ CancerResearch UK. http://www.cancerresearchuk.org/about-us/cancer-news/press-release/2014-03-24-developing-a-vaccine-for-the-epstein-barr-virus-could-prevent-up-to-200000-cancers-globally-say (March 24, 2014)
 Siouda M, Frencha C, Accardi R, et al. (2014) Epstein-Barr Virus Down-Regulates Tumor Suppressor DOK1 Expression, PLoS Pathog, 10(5): doi: 10.1371/journal.ppat.1004125
 Pender MP, and Burrows SR. (2014) Review: Epstein–Barr virus and multiple sclerosis: potential opportunities for immunotherapy, Clin Transl Immunology 3, e27; doi:10.1038/cti.2014.25
 “Cancer Facts & Figures 2015” American Cancer Society, http://www.cancer.org/research/cancerfactsstatistics/cancerfactsfigures2015/index , (2015)
 Purtilo DT, OkanoM, and Grierson HL. (1990) Immune deficiency as a risk factor in Epstein-Barr virus-induced malignant diseases , Environ Health Perspect (88): 225-230.
 Cohen JI. (2015) Epstein–bar virus vaccines, Clin & Transl Immunology. 4(1):e32-. doi:10.1038/cti.2014.27.
Sydney Saltzman is currently senior at Muhlenberg College, double majoring in Biology and Political Science.
After graduation, she hopes to go to medical school, and maybe pursue a Master of Public Health degree. She’s very interested in genetics and cancer research, and is hoping to specialize in Oncology.
This semester, she’s further pursuing that interest by doing molecular genetics research in Dr. Wightman’s lab. She’s also looking forward to spending her final semester of college combining her interests in healthcare and politics in a political science honors thesis that will investigate how the implementation of the Affordable Care Act affects poor women’s access to healthcare.